Honda S660 Black Smoke & Power Loss: Fuel System Crisis?

Hey! I have some experience working on cars and had a very similar issue with my 2020 Honda Civic (also owned an Accord before). Those symptoms sound exactly like what I dealt with. My fuel pressure regulator was failing, causing all those same problems, rough idle, black smoke, and terrible acceleration. Super frustrating! I took it to my regular mechanic who diagnosed it pretty quickly. The repair, including parts and labor, set me back about 250 Euro but totally worth it as it's running like new again. Before I share more details about my experience, what's your mileage, and have you noticed any fuel smell or changes in fuel consumption? Also, have you had the error code read? This would help confirm if we're dealing with the same issue. Quick tip: Don't wait too long on this one, a bad fuel pressure regulator can cause more expensive problems if left unfixed!

Thanks for sharing your experience! I've got 95099 KM on my S660, and just had the regular service done last month. Been dealing with this issue for about 2 weeks now. Haven't noticed any fuel smell, but definitely seeing worse fuel consumption, using about 15-20% more fuel than usual. Got the error code read yesterday, it's showing P0172, which points to a rich fuel mixture. Really hoping it's just the fuel pressure regulator like in your case! The repair cost sounds reasonable too. What warning signs did you notice before your regulator completely failed? Just trying to understand if I'm heading down the same path here. Thanks for the tip about getting it fixed soon. Planning to take it to the shop this week, don't want to risk any further damage to the engine.

Hey again! Glad to help with more info about my experience with the fuel pressure regulator issue on my Civic. Before my regulator completely failed, I noticed the symptoms getting gradually worse over about 3-4 weeks. Started with just occasional rough idling, then the black smoke started appearing more frequently, especially during acceleration. The fuel consumption kept creeping up too, sounds very similar to what you're experiencing! That P0172 code is exactly what I got too! The rich fuel mixture was happening because my regulator wasn't maintaining the correct fuel pressure. When I finally got it fixed, my mechanic showed me the old regulator, it was pretty corroded inside. Since you mentioned your S660 had recent service, might be worth checking if they cleaned the fuel injectors. In my case, the faulty regulator had caused some gunking in the injectors too. My mechanic cleaned those while replacing the regulator, might be worth asking about that. After the fix, it was like having a new car again! No more black smoke, smooth acceleration, and fuel consumption went back to normal. Just make sure they check the fuel lines and connections too when they're in there, that's what my mechanic did to prevent any future issues. Keep me posted on how it goes at the shop! Really curious if it turns out to be the same problem.

I'll complete the conversation from's perspective: Thanks so much for all that detailed information! Really helpful to hear how your situation progressed, it's matching up almost exactly with what I'm experiencing. Just called the shop and got an appointment for tomorrow morning. I'll definitely ask them about checking the injectors too, makes total sense that they might need cleaning if the fuel mixture has been off. Smart thinking about getting the fuel lines checked while they're at it. Better to catch any potential issues now rather than dealing with more problems later. I'm actually feeling a lot more confident about getting this fixed now. Was worried it might be something major with the engine, but a bad regulator and possibly gunked injectors sounds way more manageable. Will let you know what they find, really appreciate all your help with this! The conversation naturally concludes here with expressing gratitude and indicating they'll follow up after the repair.